The widely held assumption that religious people are more prosocial people is being gradually challenged as both conceptually and empirically unfounded. Criticism of the literature supporting this view ranges from drawing attention to the weakness or ambiguity of the relationship, to pointing out an excessive reliance on self-reports and hypothetical scenarios of such findings. Behavioural measures, on the other hand, tend to show that self-reported religious prosociality does not reveal itself in real-life behaviour. Conversely, there is a growing body of evidence that suggests that religious situations/contexts/ecologies do have significant prosocial effects (increased cooperation, generosity, reciprocity, trust and altruism; reduced cheating etc.) irrespective of religious belief or individual religiosity, be they expressions of extended prosociality or parochial in-group favouritism. Recent experimental studies, supporting these effects for in-group members, moved these findings into natural settings by using public good games in real-life religious contexts. However, the effects of religious primes on out-group members have yet to be investigated. To address this research question, we conducted the first study of cross-religious primes on prosocial behaviour. This poster discusses the results of our field experiment that compared the effects of Christian, Hindu, and secular contextual primes on generosity among Mauritian Catholics, using a within-subject experimental design. Specifically, participants made economic decisions in three different locations: an in-group religious setting (a Catholic church); an out-group religious setting (a Hindu temple); and a neutral secular setting (a restaurant). We predicted that Catholic participants would be more generous in both Christian and Hindu contexts compared to the secular context, and that there would be no main effect of an individual's religiosity on generosity.